Buggy code:
public class AntiEntropyService { private static final Logger logger = Logger . getLogger ( AntiEntropyService . class ) ; public static final String AE_SERVICE_STAGE = "AE-SERVICE-STAGE" ; public static final String TREE_REQUEST_VERB = "TREE-REQUEST-VERB" ; public static final String TREE_RESPONSE_VERB = "TREE-RESPONSE-VERB" ; public static final long TREE_STORE_TIMEOUT = 600000 ; public static final long NATURAL_REPAIR_FREQUENCY = 3600000 ; private static volatile AntiEntropyService aeService ; private final ConcurrentMap < AntiEntropyService . CFPair , Long > naturalRepairs ; private final Map < AntiEntropyService . CFPair , Cachetable < InetAddress , AntiEntropyService . TreePair > > trees ; public static AntiEntropyService instance ( ) { } private AntiEntropyService ( ) { } private Cachetable < InetAddress , AntiEntropyService . TreePair > rendezvousPairs ( AntiEntropyService . CFPair cf ) { } private static Collection < InetAddress > getNeighbors ( ) { } void rendezvous ( AntiEntropyService . CFPair cf , InetAddress endpoint , MerkleTree tree ) { } void notifyNeighbors ( AntiEntropyService . Validator validator , InetAddress local , Collection < InetAddress > neighbors ) { } AntiEntropyService . TreePair getRendezvousPair ( String table , String cf , InetAddress remote ) { } void clearNaturalRepairs ( ) { } private boolean shouldRunNaturally ( AntiEntropyService . CFPair cf ) { } public AntiEntropyService . IValidator getValidator ( String table , String cf , InetAddress initiator , boolean major ) { } public static interface IValidator { public void prepare ( ) { } public void add ( CompactedRow row ) { } public void complete ( ) { } } public static class Validator implements Callable < Object > , AntiEntropyService . IValidator { public final AntiEntropyService . CFPair cf ; public final MerkleTree tree ; private transient List < MerkleTree . RowHash > minrows ; private transient Token mintoken ; private transient long validated ; private transient TreeRange range ; private transient TreeRangeIterator ranges ; public static final Predicate < DecoratedKey > DKPRED = Predicates . alwaysTrue ( ) ; public static final RowHash EMPTY_ROW = new MerkleTree . RowHash ( null , new byte [ 0 ] ) ; Validator ( AntiEntropyService . CFPair cf ) { } Validator ( AntiEntropyService . CFPair cf , MerkleTree tree ) { } public void prepare ( ) { } public void add ( CompactedRow row ) { } private RowHash rowHash ( CompactedRow row ) { } public void complete ( ) { } public Object call ( ) throws Exception { } } public static class NoopValidator implements AntiEntropyService . IValidator { public void prepare ( ) { } public void add ( CompactedRow row ) { } public void complete ( ) { } } public static class Differencer implements Runnable { public final AntiEntropyService . CFPair cf ; public final InetAddress local ; public final InetAddress remote ; public final MerkleTree ltree ; public final MerkleTree rtree ; public final List < MerkleTree . TreeRange > differences ; public Differencer ( AntiEntropyService . CFPair cf , InetAddress local , InetAddress remote , MerkleTree ltree , MerkleTree rtree ) { } public void run ( ) { } float differenceFraction ( ) { } void performRangeRepair ( ) throws IOException { } void performStreamingRepair ( ) throws IOException { AntiEntropyService . logger . info ( ( ( ( ( ( "Performing<seq2seq4repair_space>streaming<seq2seq4repair_space>repair<seq2seq4repair_space>of<seq2seq4repair_space>" + ( differences . size ( ) ) ) + "<seq2seq4repair_space>ranges<seq2seq4repair_space>to<seq2seq4repair_space>" ) + ( remote ) ) + "<seq2seq4repair_space>for<seq2seq4repair_space>" ) + ( cf ) ) ) ; ColumnFamilyStore cfstore = Table . open ( cf . left ) . getColumnFamilyStore ( cf . right ) ; try { List < Range > ranges = new ArrayList < Range > ( differences ) ; <START_BUG> List < SSTableReader > sstables = instance . submitAnti ( cfstore , ranges , remote ) . get ( ) ; <END_BUG> Streaming . transferSSTables ( remote , sstables , cf . left ) ; } catch ( Exception e ) { throw new IOException ( "Streaming<seq2seq4repair_space>repair<seq2seq4repair_space>failed." , e ) ; } AntiEntropyService . logger . debug ( ( ( ( "Finished<seq2seq4repair_space>streaming<seq2seq4repair_space>repair<seq2seq4repair_space>to<seq2seq4repair_space>" + ( remote ) ) + "<seq2seq4repair_space>for<seq2seq4repair_space>" ) + ( cf ) ) ) ; } public String toString ( ) { } } public static class TreeRequestVerbHandler implements ICompactSerializer < AntiEntropyService . CFPair > , IVerbHandler { public static final AntiEntropyService . TreeRequestVerbHandler SERIALIZER = new AntiEntropyService . TreeRequestVerbHandler ( ) ; static Message makeVerb ( String table , String cf ) { } public void serialize ( AntiEntropyService . CFPair treerequest , DataOutputStream dos ) throws IOException { } public AntiEntropyService . CFPair deserialize ( DataInputStream dis ) throws IOException { } public void doVerb ( Message message ) { } } public static class TreeResponseVerbHandler implements ICompactSerializer < AntiEntropyService . Validator > , IVerbHandler { public static final AntiEntropyService . TreeResponseVerbHandler SERIALIZER = new AntiEntropyService . TreeResponseVerbHandler ( ) ; static Message makeVerb ( InetAddress local , AntiEntropyService . Validator validator ) { } public void serialize ( AntiEntropyService . Validator v , DataOutputStream dos ) throws IOException { } public AntiEntropyService . Validator deserialize ( DataInputStream dis ) throws IOException { } public void doVerb ( Message message ) { } } static final class CFPair extends Pair < String , String > { public CFPair ( String table , String cf ) { } } static final class TreePair extends Pair < MerkleTree , MerkleTree > { public TreePair ( MerkleTree local , MerkleTree remote ) { } } }

Fix:
List < SSTableReader > sstables = instance . submitAnticompaction ( cfstore , ranges , remote ) . get ( ) ;